lib: Create API to read the RSSI of a BLE device

2 files changed, 62 insertions, 1 deletions

diff --git a/lib/ble.c b/lib/ble.c
index 5e71355..cd76ee4 100644
--- a/lib/ble.c
+++ b/lib/ble.c
@@ -308,6 +308,46 @@ static ble_device_t *find_device_by_conn_id(int conn_id) {
     return dev;
 }
 
+/* Called in response of a read remote RSSI operation */
+void read_remote_rssi_cb(int client_if, bt_bdaddr_t *bda, int rssi,
+                         int status) {
+    ble_device_t *dev;
+    int conn_id = -1;
+
+    if (!status) {
+        dev = find_device_by_address(bda->address);
+        if (dev)
+            conn_id = dev->conn_id;
+    }
+
+    if (data.cbs.rssi_cb)
+        data.cbs.rssi_cb(conn_id, rssi, status);
+}
+
+int ble_read_remote_rssi(int conn_id) {
+    ble_device_t *dev;
+    bt_status_t s;
+
+    if (!data.client)
+        return -1;
+
+    if (conn_id <= 0)
+        return -1;
+
+    if (!data.gattiface)
+        return -1;
+
+    dev = find_device_by_conn_id(conn_id);
+    if (!dev)
+        return -1;
+
+    s = data.gattiface->client->read_remote_rssi(data.client, &dev->bda);
+    if (s != BT_STATUS_SUCCESS)
+        return -s;
+
+    return 0;
+}
+
 static int find_service(ble_device_t *dev, btgatt_srvc_id_t *srvc_id) {
     int id;
 
@@ -799,7 +839,7 @@ static const btgatt_client_callbacks_t gattccbs = {
     read_descriptor_cb,
     write_descriptor_cb,
     NULL, /* execute_write_cb */
-    NULL, /* read_remote_rssi_cb */
+    read_remote_rssi_cb
 };
 
 /* GATT interface callbacks */
diff --git a/lib/ble.h b/lib/ble.h
index 8d072ad..b2e1618 100644
--- a/lib/ble.h
+++ b/lib/ble.h
@@ -106,6 +106,17 @@ typedef void (*ble_bond_state_cb_t)(const uint8_t *address,
                                     ble_bond_state_t state, int status);
 
 /**
+ * Type that represents a callback function to inform the RSSI of the remote
+ * BLE device.
+ *
+ * @param conn_id The identifier of the connected remote device.
+ * @param rssi The RSSI of the remote device.
+ * @param status The status in which the read remote RSSI operation has
+ *               finished.
+ */
+typedef void (*ble_rssi_cb_t)(int conn_id, int rssi, int status);
+
+/**
  * Type that represents a callback function to notify of a new GATT element
  * (service, characteristic or descriptor) found in a BLE device.
  *
@@ -185,6 +196,7 @@ typedef struct ble_cbs {
     ble_connect_cb_t connect_cb;
     ble_connect_cb_t disconnect_cb;
     ble_bond_state_cb_t bond_state_cb;
+    ble_rssi_cb_t rssi_cb;
     ble_gatt_found_cb_t srvc_found_cb;
     ble_gatt_finished_cb_t srvc_finished_cb;
     ble_gatt_found_cb_t char_found_cb;
@@ -303,6 +315,15 @@ int ble_cancel_pairing(const uint8_t *address);
 int ble_remove_bond(const uint8_t *address);
 
 /**
+ * Read the RSSI of a remote BLE device.
+ *
+ * There should be an active connection with the device.
+ *
+ * @param conn_id The identifier of the connected remote device.
+ */
+int ble_read_remote_rssi(int conn_id);
+
+/**
  * Discover services in a BLE device.
  *
  * There should be an active connection with the device.